line_max_width

Cap line length in characters (not bytes — code points). Optional tab_width for tab expansion.

A text file with stray invalid UTF-8 is measured (each invalid byte counts as one column) rather than skipped; binary-looking files are skipped.

Options

Option	Type	Required	Default	Description
max_width	integer (>= 1)	yes		Maximum number of Unicode scalar values (chars) allowed per line.

Plus the common paths, level, id, when, scope_filter, and expect_matches fields. This table is generated from the JSON Schema; option types and defaults are authoritative.

Example

A source file with a line past the width limit

The rule fires on this repository:

• src/
• src/ok.rs✓
• src/wide.rs⚠

  ⚠ warning narrow

  2:31 line 2 is 72 chars wide; max is 30

src/ok.rs

fn a() {}
fn b() {}

src/wide.rs

fn x() {}
this line is intentionally way too long to be acceptable under the limit
fn y() {}

With this .alint.yml:

version: 1
rules:
  - id: narrow
    kind: line_max_width
    paths: "src/**/*.rs"
    max_width: 30
    level: warning

alint check reports:

--- src/wide.rs ----------------------------------------------------------------
  !  warning  narrow
              2:31  line 2 is 72 chars wide; max is 30

Summary (1 violation):
  ! 1 warning
  0 passing * 1 failing

Every line stays within the width limit

This repository is compliant:

• src/
• src/a.rs✓
• src/b.rs✓

src/a.rs

fn a() {}
fn b() {}

src/b.rs

pub fn c() {}

With this .alint.yml:

version: 1
rules:
  - id: narrow
    kind: line_max_width
    paths: "src/**/*.rs"
    max_width: 30
    level: warning

alint check reports:

v All 1 rule(s) passed.